Answer:

Explanation:
Hello,
In this case, considering that the density of a body is computed given its mass and volume:

Taking into account that the mass is 24.32 g and the volume is computed via the difference between the volume of the water with the brass and the volume of water by itself as follows:

The density of the piece of brass turns out:

Best regards.
From the equation:
1 mole Fe₂O₃ needs 3 moles of CO
1.75 moles require:
1.75 x 3
= 5.25 moles of CO
Answer:
Option a: positron emission.
Explanation:
In the transformation we have:
⁶⁷Ga → ⁶⁷Zn
The reaction is:

For Ga to become Zn, the atom nucleus has to lose a proton, so in the given options, the reaction that involves the transformation of a proton is the option a, positron emission.
In a positron emission, a proton becomes into a neutron and a positron:

Therefore, the correct answer is option a: positron emission.
I hope it helps you!
Answer:
0.500 mol/dm³
Explanation:
Using the formula below;
CaVa = CbVb
Where;
Ca = concentration of acid (mol/dm³)
Cb = concentration of base (mol/dm³)
Va = volume of acid (cm³)
Vb = volume of base (cm³)
In accordance to the information provided in this question is;
Va = 5cm³
Vb = 250 cm³
Ca = 12 mol/dm³
Cb = ?
Using CaVa = CbVb
12 × 5 = Cb × 250
60 = 120Cb
Cb = 60/120
Cb = 0.500 mol/dm³